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Examination of Thymic Positive and Negative Selection by Flow Cytometry
Published on: October 8, 2012
A critical role for CD2 in both thymic selection events and mature T cell function
1Laboratory of Immunobiology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
Journal of Immunology (Baltimore, Md. : 1950)
|February 13, 2001
Summary
CD2 plays a crucial role in T cell development and function. Its absence impairs thymic development and reduces mature T cell responsiveness to antigens, impacting immune cell signaling.
Area of Science:
- Immunology
- Molecular Biology
- Cell Biology
Background:
- CD2 is a cell surface glycoprotein involved in T cell activation.
- Its precise in vivo functions, particularly during thymocyte development and T cell responses, require further elucidation.
Purpose of the Study:
- To investigate the in vivo role of CD2 in T cell receptor (TCR) signaling and thymocyte development.
- To assess the impact of CD2 deficiency on T cell responsiveness to specific peptide antigens.
Main Methods:
- Utilized N15 TCR transgenic (tg) RAG-2(-/-) mice on wild-type and CD2(-/-) backgrounds.
- Analyzed thymocyte development, T cell populations, and cytokine production (IFN-gamma).
- Performed repertoire analysis of T cell receptor Valpha usage.
Main Results:
- CD2 deficiency in N15tg mice led to thymic dysfunction and a pre-TCR block at the CD4(-)CD8(-) double-negative stage.
- Mature CD2(-/-) T cells exhibited significantly reduced responsiveness to cognate and weak peptide agonists.
- Differences in Valpha usage were observed between wild-type and CD2(-/-) mice.
Conclusions:
- CD2 is essential for proper pre-TCR function in double-negative thymocytes.
- CD2 influences TCR selection during thymocyte development.
- CD2 plays a significant role in TCR-stimulated cytokine production in mature T cells.
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